Effect of Diluent on the Extraction of Oxoethanoic (Glyoxylic) Acid by N,N-Dioctyloctan-1-amine (TOA)

Abstract

The extractability of aqueous solutions of oxoethanoic acid by N,N-dioctyloctan-1-amine (TOA) in various diluents, including isoamyl alcohol, octan-1-ol, nonan-1-ol, decan-1-ol, methyl ethyl ketone, diisobuthyl ketone, hexan-2-one, toluene, kerosene, and n-hexane has been investigated. Batch extraction results at 25 degrees C have been calculated and reported as distribution coefficients (K-D), loading factors (Z), and extraction efficiencies (E). With these solvents, using TOA has been found to be very effective (K-D >> 1). Decan-1-ol was found to be the most effective diluent with the highest value of K-D (13.43) at 1.37 mol.kg(-1) concentration of TOA. The results of the liquid-liquid equilibrium measurements were correlated with a linear solvation energy relationship (LSER) model that takes into account physical interactions as well as with modified Freundlich and Langmuir equations. The experimental results for the oxoethanoic acid extraction are compared to the model results.